Relation between blood lipids, lipoproteins, and cerebrovascular atherosclerosis. A review

Association between miR-365 polymorphism and ischemic stroke in a Chinese population

Background

Ischemic stroke (IS) represents a major cause of morbidity and mortality across the globe. The aberrant expression of miR-365 has been found to be implicated in a wide array of human diseases, including atherosclerosis and cancer. Studies on single-nucleotide polymorphisms (SNPs) in miRNA genes can help gain insight into the susceptibility to the condition. This study aimed to examine the relationship between miR-365 SNPs and the risk of IS.

Methods

The study recruited 215 IS patients and 220 controls. The SNPscans genotyping was employed to genotype three polymorphic loci (rs121224, rs30230, and rs178553) of miR-365. The relative expression of miR-365 in peripheral blood mononuclear cells of the patients and controls was determined by using real-time quantitative PCR.

Results

The miR-365 rs30230 polymorphism exhibited a significant association with the risk of developing IS (TC vs. CC: adjusted OR = 0.55, 95% CI: 0.33-0.92, P = 0.022; TT vs. CC: adjusted OR = 0.34, 95% CI: 0.14-0.85, P = 0.021; TC +TT vs. CC: adjusted OR = 0.51, 95% CI: 0.31-0.83, P = 0.007; T vs. C: adjusted OR = 0.57, 95% CI: 0.39-0.83, P = 0.004). Haplotype analysis revealed that the C-T-G haplotype was associated with a decreased risk of IS (OR = 0.68, 95% CI: 0.46-1.00, P = 0.047). Furthermore, miR-365 expression was significantly higher in IS patients than in controls (P < 0.001). Interestingly, patients with rs30230 TC or TT genotypes had lower miR-365 levels compared to their counterparts with CC genotypes (P < 0.001).

Conclusions

The miR-365 rs30230 polymorphism might bear an association with IS susceptibility in the Chinese population, and the rs30230 TC/TT genotype might be a protective factor against IS.

A genetic variant in the promoter of lncRNA MALAT1 is related to susceptibility of ischemic stroke

Background

Metastasis-associated lung adenocarcinoma transcript-1 (MALAT1) was aberrantly expressed in diverse diseases. Particularly in ischemic stroke (IS), the abnormal expression of MALAT1 played important roles including promotion of angiogenesis, inhibition of apoptosis and inflammation and regulation of autophagy. However, the effects of genetic variation (single nucleotide polymorphisms, SNPs) of MALAT1 on IS have rarely been explored. This study aimed to investigate whether SNPs in promoter of MALAT1 were associated with the susceptibility to IS.

Methods

A total of 316 IS patients and 320 age-, gender-, and ethnicity-matched controls were enrolled in this study. Four polymorphisms in the promoter of MALAT1 (i.e., rs600231, rs1194338, rs4102217, and rs591291) were genotyped by using a custom-by-design 48-Plex SNPscan kit.

Results

The rs1194338 C > A variant in the promoter of MALAT1 was associated with the risk of IS (AC vs. CC: adjusted OR = 0.623, 95% CI, 0.417–0.932, P = 0.021; AA vs. CC: adjusted OR = 0.474, 95% CI, 0.226–0.991, P = 0.047; Dominant model: adjusted OR = 0.596, 95% CI, 0.406–0.874, P = 0.008; A vs. C adjusted OR = 0.658, 95% CI, 0.487–0.890, P = 0.007). The haplotype analysis showed that rs600231-rs1194338-rs4102217-rs591291 (A-C-G-C) had a 1.3-fold increased risk of IS (95% CI, 1.029–1.644, P = 0.027). Logistic regression analysis identified some independent impact factors for IS including rs1194338 AC/AA, TC, TG, HDL-C, LDL-C, Apo-A1, Apo-B and NEFA (P < 0.05).

Conclusions

These results suggest that the rs1194338 AC/AA genotypes may be a protective factor for IS.

Amygdalin ameliorates the progression of atherosclerosis in LDL receptor‑deficient mice

Previous studies have demonstrated that regulatory T cells (Tregs) are pivotal in the regulation of T cell-mediated immune responses in atherosclerosis, a chronic autoimmune-like disease. In the authors' previous studies, it was demonstrated that amygdalin ameliorated atherosclerosis by the regulation of Tregs in apolipoprotein E-deficient (ApoE^−/−) mice. Therefore, the aim of the present study was to investigate the therapeutic effect of amygdalin on low-density lipoprotein (LDL) receptor deficient (LDLR^−/−) mice, and to examine its immune regulatory function by the stimulation of Tregs. To establish an atherosclerosis mouse model, the LDLR^−/− mice were fed a high fat and high cholesterol diet then the total plasma cholesterol, triglyceride, LDL and chemokines levels were measured by an ELISA. Following sacrificing the mice, the upper sections of the aorta were stained by hematoxylin and eosin, and Oil red O to assess the plaque area. Then western blotting and reverse transcription polymerase chain reactions were performed to analysis the expression levels of cluster of differentiation 68, monocyte chemoattractant protein-1, matrix metalloproteinase (MMP)-2, MMP-9 and forkhead box P3 (Foxp3). To further confirm the activation of FOXP3 by amygdalin, lentiviruses carrying Foxp3 shRNA were injected into the mice, and the serum cytokines levels were measured by ELISA. Following feeding of the mice with a high-fat/high-cholesterol diet, the LDLR^−/− mice demonstrated comparatively higher levels of triglyceride, total cholesterol and LDL, compared with levels in the amygdalin-treated mice. By comparing the vessel area, lumen area, plaque area, and percentage aortic plaque coverage, the effects of amygdalin on pre-existing lesions were assessed. In addition, the levels of CD68, monocyte chemoattractant protein-1, MMP-2 and MMP-9 were analyzed, and analysis of the expression of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α indicated that the mice treated with amygdalin had decreased expression of pro-inflammatory cytokines. The mRNA and protein levels of Foxp3 were also quantified, and the mice treated with amygdalin demonstrated an increased number of Tregs. The knockdown of Foxp3mRNA resulted in the increased secretion of IL-1β, IL-6 and TNF-α. Therefore, the data indicated that amygdalin regulated the formation of atherosclerosis and stabilized the plaque by suppressing inflammatory responses and promoting the immune-modulation function of Tregs. Taken together, the results demonstrated the therapeutic effect of amygdalin on atherosclerosis.

Comparison of Risk Factor between Lacunar Stroke and Large Artery Atherosclerosis Stroke: A Cross-Sectional Study in China

Background

Stroke is the second most common cause of mortality in China. Although most subtypes of ischemic stroke share similar risk factors, they have different etiologies. Our study aimed to evaluate the different risk factor profiles between the stroke subtypes, lacunar infarcts (LI) and large-artery atherosclerosis (LAA), and clarify the characteristics of current acute ischemic stroke in China.

Methods

In this cross-sectional study, we analyzed the clinical characteristics of 1982 patients with acute ischemic stroke who were admitted to the neurology department at the Peking University First Hospital between 2007 and 2014. Ischemic stroke was further classified into LAA, LI, cardioembolism (CE) and undetermined causes of infarction (UDI) according to TOAST classification. Demographic characteristics, risk factors, as well as the findings of laboratory and imaging tests of 1773 patients with LAA and LI, were analyzed by univariate and multivariate logistic analysis.

Results

Of the 1982 ischemic stroke patients included in this study, 1207 were diagnosed with LAA, 566 with LI, 173 with cardioembolism (CE) and 36 with undetermined causes of infarction (UDI). By comparing the risk factors in multivariate logistic regression analysis, hypertension [odds ratio (OR) = 1.832] and white matter leukoaraiosis (WML) (OR = 1.865) were found to be more strongly correlated with LI than LAA. Low density lipoprotein- cholesterol (LDL-c) (OR = 0.774) were more strongly related to LAA than LI.

Conclusions

This study found that hypertension and WML were more strongly correlated with LI than LAA. LDL-c was more strongly related to LAA than LI.

Preventing vascular effects on brain injury and cognition late in life: knowns and unknowns

For some researchers, the relationship between prevalent cardiovascular risk factors and late-life cognitive decline is not worthy of further study. It is already known that effective treatment of vascular risk factors lowers risk of such major outcomes as stroke and heart attack, the argument goes; thus, any new information about the relationship between vascular risk factors and another major outcome--late-life cognitive decline--is unlikely to have an impact on clinical practice. The purpose of this review is to probe the logic of this argument by focusing on what is known, and what is not known, about the relationship between vascular risk factors and late-life cognitive decline. The unknowns are substantial: in particular, there is relatively little evidence that current vascular risk factor treatment protocols are adequate to prevent late-life cognitive decline or the clinically silent brain injury that precedes it. In addition, there is relatively little understanding of which factors lead to differential vulnerability or resilience to the effects of vascular risk factors on silent brain injury. Differential effects of different classes of treatments are similarly unclear. Finally, there is limited understanding of the impact of clinically-silent neurodegenerative disease processes on cerebrovascular processes. Further study of the relationships among vascular risk factors, brain injury, and late-life cognitive decline could have a major impact on development of new vascular therapies and on clinical management of vascular risk factors, and there are promising avenues for future research in this direction.

Independent and interactive effects of blood pressure and cardiac function on brain volume and white matter hyperintensities in heart failure

BACKGROUND

Reduced systemic perfusion and comorbid medical conditions are key contributors to adverse brain changes in heart failure (HF). Hypertension, the most common co-occurring condition in HF, accelerates brain atrophy in aging populations. However, the independent and interactive effects of blood pressure and systemic perfusion on brain structure in HF have yet to be investigated.

METHODS

Forty-eight older adults with HF underwent impedance cardiography to assess current systolic blood pressure status and cardiac index to quantify systemic perfusion. All participants underwent brain magnetic resonance imaging to quantify total brain, total and subcortical gray matter volume, and white matter hyperintensities (WMH) volume.

RESULTS

Regression analyses adjusting for medical and demographic factors showed decreased cardiac index was associated with smaller subcortical gray matter volume (P < .01), and higher systolic blood pressure predicted reduced total gray matter volume (P = .03). The combination of higher blood pressure and lower cardiac index exacerbated WMH (P = .048).

CONCLUSIONS

Higher blood pressure and systemic hypoperfusion are associated with smaller brain volume, and these factors interact to exacerbate WMH in HF. Prospective studies are needed to clarify the effects of blood pressure on the brain in HF, including the role of long-term blood pressure fluctuations.

Aggressive statin treatment, very low serum cholesterol levels and haemorrhagic stroke: is there an association?

PURPOSE OF REVIEW

To assess the potential association between haemorrhagic stroke and achieving very low serum cholesterol levels with aggressive statin treatment.

RECENT FINDINGS

The Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) study showed a reduction in both fatal and nonfatal stroke but an increase in the risk for haemorrhagic stroke during high-dose atorvastatin treatment. However, post-hoc analyses of this trial showed that this increased risk is primarily observed in elderly men with a history of haemorrhagic stroke. In addition, there was no relationship between baseline or on-treatment low-density lipoprotein cholesterol (LDL-C) levels and haemorrhagic stroke.

SUMMARY

Existing data suggest that low LDL-C levels during intensive statin treatment are not associated with an increased risk for haemorrhagic stroke, except in patients with a history of intracerebral haemorrhage. In patients with a history of ischaemic stroke, intensive statin treatment substantially reduces the risk for both recurrent ischaemic stroke and for coronary heart disease (CHD) events. Any possible excess of haemorrhagic stroke is greatly outweighed by the protective effect against ischaemic stroke and CHD events.

Cholesterol-lowering interventions and stroke: insights from a meta-analysis of randomized controlled trials

OBJECTIVES

This meta-analysis was performed to determine the effects of various cholesterol-lowering treatments on the risk of stroke and its relationship with the extent of cholesterol lowering.

BACKGROUND

Statins reduce the incidence of stroke, and it has been proposed that such effect is independent of cholesterol lowering and is explained by alternative mechanisms.

METHODS

We performed a meta-analysis of randomized trials of cholesterol-lowering treatments in cardiovascular disease reporting on stroke, involving 266,973 patients investigated and a cumulative 946,582 person-years of exposure, and a meta-regression analysis of the extent of stroke reduction as a function of changes in total cholesterol.

RESULTS

The odds ratio (OR) for the incidence of stroke in actively treated groups versus controls was 0.88 (95% confidence interval: 0.83 to 0.94, p < 0.001). No treatment affected fatal strokes. Whereas statins decreased the risk of total stroke significantly (OR: 0.85, 95% confidence interval: 0.78 to 0.92; p < 0.001), the benefit of nonstatin interventions was smaller and not statistically significant (diet OR: 0.92, fibrates OR: 0.98, other treatments OR: 0.81). We found a significant relationship between percent reduction of total (and low-density lipoprotein) cholesterol and percent reduction of total strokes (p = 0.0017), with each 1% reduction of total cholesterol predicting a 0.8% relative risk reduction of stroke. We found no significant association between stroke reduction and changes of high-density lipoprotein cholesterol levels, and inconsistent associations with reduction of triglycerides.

CONCLUSIONS

Among cholesterol-lowering treatments, statins are the most effective at decreasing the risk of total stroke, but their benefit is proportional to the percent reduction of total cholesterol and low-density lipoprotein cholesterol. No lipid-lowering intervention was associated with a reduction of fatal stroke.

Blood lipids in brain infarction subtypes

BACKGROUND

Little is known about the relationship between hypercholesterolaemia and specific aetiological subtypes of brain infarction (BI).

METHODS

In a cross-sectional study of 492 pairs of patients with a BI proven by MRI and matched hospital controls, we determined the blood levels of triglycerides, total, HDL and LDL cholesterol, and apolipoprotein A(1) and B, in the same centralized laboratory. We performed aetiological BI subtype classification.

RESULTS

Except for triglycerides, the risk of BI increased continuously with the lipid levels, without any heterogeneity between the main BI subtypes or the group on lipid-lowering therapy. The adjusted odds ratio per standard deviation in LDL cholesterol (0.93 mmol/l) was 1.74 (95% confidence interval, 1.02-2.98) in atherothrombotic strokes (n = 109) and 2.71 (95% confidence interval, 1.60-4.55) in lacunar strokes (n = 105). Eighty percent of patients were above the ATP-III guideline threshold LDL cholesterol of 2.59 mmol/l (100 mg/dl), with a major contribution of both atherothrombotic and lacunar stroke subtypes to this group.

CONCLUSIONS

These findings suggest that blood lipids, particularly total and LDL cholesterol levels, are associated with all subtypes of BI, and that LDL above 2.59 mmol/l is highly prevalent.

Cholesterol in neurologic disorders of the elderly: stroke and Alzheimer’s disease

Mechanisms for the regulation of intracellular cholesterol levels in various types of brain and vascular cells are of considerable importance in our understanding of the pathogenesis of a variety of diseases, particularly atherosclerosis and Alzheimer's disease (AD). It is increasingly clear that conversion of brain cholesterol into 24-hydroxycholesterol and its subsequent release into the periphery is important for the maintenance of brain cholesterol homeostasis. Recent studies have shown elevated plasma concentrations of 24-hydroxycholesterol in patients with AD and vascular dementia, suggesting increased brain cholesterol turnover during neurodegeneration. The oxygenases involved in the degradation and excretion of cholesterol, including the cholesterol 24-hydroxylase and the 27-hydroxylase, are enzymes of the cytochrome P-450 family. This review focuses on the newly recognized importance of cholesterol and its oxygenated metabolites in the pathogenesis of ischemic stroke and AD. The reduction in stroke and AD risk in patients treated with cholesterol-lowering statins is also discussed.

Links between the pathology of Alzheimer's disease and vascular dementia

The major neuropathological lesions defining Alzheimer's disease (AD) include neurofibrillary tangles and amyloid plaques, which are mainly composed of abnormally phosphorylated tau and amyloid-beta (A beta), respectively. Numerous neuropathological and neuroimaging studies indicate that at least one-third of AD cases are complicated by some degree of vascular pathology, whereas in a similar proportion of patients clinically diagnosed with vascular dementia, AD pathology is also present. Many classical vascular risk factors such as hypertension, diabetes mellitus, and hypercholesterolemia have recently been shown also to increase the risk of AD. Growing evidence suggests that vascular pathology lowers the threshold for the clinical presentation of dementia at a given level of AD-related pathology and potentially directly promotes AD lesions such as A beta plaques. Cerebral ischemia, chronically up-regulates expression of the amyloid precursor protein (APP), which is the precursor to the amyloid beta peptide and damages the blood-brain barrier (BBB), affecting A beta peptide clearance from the brain. Recognition of the importance of these vascular risk factors for AD-related dementia and their treatment will be beneficial not only for preventing cardiac, cerebral, and peripheral complications of vascular disease, but also will likely have a direct impact on the occurrence of sporadic AD in older subjects. In this paper, we review some of the links between vascular risk factors and AD pathology and present data on the direct effect of ischemia on cognitive function and A beta deposition in a mouse model of AD.

Minor thalassemia as a protective factor against cerebrovascular accidents

Hypertension, hypercholesterolemia, and coronary artery disease are among the risk factors of cerebrovascular accidents. After age, hypertension is the most powerful stroke risk factor. Abnormalities of serum lipids are regarded as risk factors for cerebrovascular accidents. A significant reduction in stroke risk among persons treated with cholesterol-reducing medicines known as statins are reported. Stroke risk nearly doubles in those with antecedent coronary artery disease. Moreover, polycythemia and high hematocrit levels are considered to be potential stroke risk factors. Minor thalassemia is associated with decreased prevalence of arterial hypertension and myocardial infarction (the second effect observed only in males.) Total cholesterol and LDL levels are lower in minor thalassemics, as is the blood viscosity. Therefore, it could be hypothesized that minor thalassemia could afford some protection against cerebrovascular accidents.

Relation of lipid and lipoprotein(a) to ischaemic stroke

The relationship of lipids and Lp(a) to ischemic stroke hasn't been established yet. Our aim was to determine lipid profile and vascular risk factors in stroke patients and compare them with control subjects. Seventy-nine consecutive patients with ischemic stroke were analyzed by total cholesterol, HDL-C, LDL-C, triglyceride, Lp(a) and doppler ultrasonography and vascular risk factors were recorded. Thirty control subjects of same ages were compared with the patient group. Lp(a) and lipids were correlated with stroke subtype and carotid atherosclerosis. There was no statistical significance between patients and control subjects related to total cholesterol, triglyceride, HDL-C, LDL-C and Lp(a) (P>0.05). Atherotrombotic and lacunar strokes didn't show any difference correlated with lipids and Lp(a). Hypertension and diabetes mellitus were important risk factors with (OR=4.50, 95% CI=1.25-16.22) and (OR=4.43, 95% CI=1.79-10.93) respectively. These results were statistically significant (P<0.05). Total cholesterol (308.67+/-85.82) and Lp(a) (32.10+/-17.30) values showed statistical significance (P<0.05) in patients with marked stenosis when compared with patients of normal doppler ultrasonography. Hypertension and diabetes mellitus were found as independent risk factors for ischemic stroke. Lipids and Lp(a) were not independent for atherotrombotic and lacunar stroke. Lp(a) concentration and carotid atherosclerosis in ultrasonography were associated significantly.

LPL polymorphism predicts stroke risk in men

Variation in lipid levels has been associated with atherosclerotic vascular disease, including stroke. Genes contributing to interindividual variation in lipid levels may play a role in the etiology of stroke, either through their effects on lipid synthesis and metabolism or through separate pathways. For this reason, we sought to examine the association between polymorphisms in the lipoprotein lipase (LPL) and apolipoprotein E (APOE) genes and subclinical and clinical stroke in the Atherosclerosis Risk in Communities (ARIC) Study. Subclinical stroke was determined by cerebral magnetic resonance imaging (MRI). Subclinical cerebral infarct cases (n = 197) were compared to a stratified random sample identified from individuals participating in the MRI examination (n = 200). Incidence of clinical ischemic stroke was determined by following the ARIC cohort for an average of 7.5 years for potential cerebrovascular events; 218 validated clinical ischemic strokes were identified. A stratified random sample of the ARIC cohort (CRS, n = 964) was used as the comparison group for clinical cases. The LPL S291-carrying genotypes and APOE epsilon2- and epsilon4-carrying genotypes were not significantly associated with subclinical or clinical stroke. The LPL X447-containing genotypes were significantly associated with subclinical (odds ratio [OR], 4.32; 95% confidence interval [CI], 1.23-15.15; P = 0.020) and clinical stroke (hazard rate ratio [HRR], 2.57; 95% CI, 1.24-5.34; P = 0.01) in men, both by themselves and after adjustment for multiple stroke risk factors. The LPL S447X polymorphism is significantly associated with subclinical cerebral infarction and incident clinical ischemic stroke in men from a middle-aged American population. This association does not appear to be mediated by triglyceride, high-density lipoprotein (HDL)- and low-density lipoprotein (LDL)-cholesterol levels, or additional stroke risk factors.

Clinicopathological significance of lipid peroxidation in carotid plaques

Several reports have suggested an association between lipid peroxidation and human carotid atherosclerosis, but few reports have demonstrated a link between lipid peroxidation and carotid plaques in humans. In this study, we investigated the relationship between clinical features, histopathological characteristics and lipid peroxidation in patients undergoing carotid endarterectomy (CEA). Forty-one carotid plaques were obtained. A portion of the most severe lesions was subjected to histopathologic examination, and the remainder of the plaques examined for lipid peroxidation. Thiobarbituric acid-reactive substances (TBARS) values were determined as a marker for lipid peroxidation. The lipid-rich core (LC) and macrophage infiltration (Mphi) component as a percentage of total plaque area were measured morphometrically. Based on the results, all plaques were classified into four groups. Group I (GI): LC <10%; Group IIa (GIIa): LC 10-30%, Mphi <5%; Group IIb (GIIb): LC 10-30%, Mphi < or = 5%, and Group III (GIII): LC < or =30%. The plaque TBARS values of GIII were significantly higher than those of GI, GIIa, and GIIb. The TBARS values of GIIb were one-and-a-half times higher than those of GIIa. Our results show that lipid peroxidation in carotid plaques is significantly associated with carotid atherosclerosis, especially plaque instability. These findings provide direct evidence of an association between lipid peroxidation and human atherosclerosis.

Cerebral atherosclerosis occurs spontaneously in homozygous WHHL rabbits

We demonstrated that selectively bred homozygous WHHL rabbits known to show hypercholesterolemia and severe coronary atherosclerosis also spontaneously develop cerebral atherosclerosis beginning at 9 months of age. These intracranial lesions occurred in the absence of hypertension in 24 of 25 animals at various sites, mainly along arteries at the base of the brain. No lesions were observed in penetrating arteries. Lesions were rich in smooth muscle cells and fibrous tissue, showing only rare fragmentation or disappearance of the internal elastic lamina, and only limited lipid deposition. Few macrophages were observed in these lesions. No significant correlation was seen between severity of cerebral atherosclerosis and age, systolic blood pressure (BP), serum total cholesterol, or triglyceride concentration. Xanthomas of the pia mater were observed in all 25 rabbits. Arterial findings were similar to those in human cerebral atherosclerosis, indicating that the coronary atherosclerosis-prone homozygous WHHL rabbit represents the first animal model for spontaneous cerebral atherosclerosis.

The relationship between cholesterol and stroke: implications for antihyperlipidaemic therapy in older patients

Various studies on the relationship between serum cholesterol level and the risk of stroke have been published recently. Subsequent reviews have extrapolated information on stroke from the clinical trials originally aimed at lowering cholesterol for the primary and secondary prevention of myocardial infarction (MI) in middle-aged patients. We have reviewed the epidemiological knowledge on the relationship between serum cholesterol levels and stroke, and also focused on possible reduction of the risk of stroke with hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitor treatment. Possible benefits from such therapy are particularly relevant for the elderly population which is at particularly high risk for stroke. The effects of serum cholesterol levels on the risk for haemorrhagic and ischaemic stroke have been evaluated. Indirect epidemiological evidence indicates that serum levels of total cholesterol and its subfractions are determinants of stroke, but their associations are relatively weak. When exploring the possible association of serum cholesterol levels with the increased risk of stroke with aging, we concluded that, as in younger adults, elevated total cholesterol and decreased high density lipoprotein-cholesterol levels predispose to ischaemic stroke in the elderly. The mechanism through which serum cholesterol levels increase stroke risk is based on its actions on the artery walls. Indirect evidence suggests that the reduction in the stroke risk with HMG-CoA reductase inhibitors is larger than would be expected with reduction of elevated serum cholesterol level alone. Therefore, antioxidant and endothelium-stabilising properties of HMG-CoA reductase inhibitors may contribute in reducing the risk of stroke in recipients. Lowering high serum cholesterol with HMG-CoA reductase inhibitors has been beneficial in the primary and secondary prevention of MI. No trials have specifically tested the effect of cholesterol lowering with HMG-CoA reductase inhibitors on stroke occurrence. High serum cholesterol levels are a risk factor for ischaemic stroke, although the risk imparted is lower than that for MI. Although the relative risk of stroke associated with elevated serum cholesterol levels is only moderate, its population attributable risk is high given the increase in the elderly population worldwide. The effect of cholesterol reduction with HMG-CoA reductase inhibitors on prevention of ischaemic stroke should be evaluated in prospective, randomised, placebo-controlled trials in the elderly. The tolerability of lipid-lowering drugs in the elderly and the cost effectiveness of primary prevention of stroke using lipid-lowering drugs also needs to be assessed in the elderly.

Serum lipids in young patients with ischaemic stroke: a case-control study

OBJECTIVES

The relation between serum lipids and ischaemic stroke remains controversial. Studies of lipid related risk factors in cerebrovascular disease have varied greatly in their findings and also in their definition of the cerebrovascular end points. Serum lipids are thought to interact with the pathogenesis of stroke through an atherosclerosis mechanism. Stroke in young patients have been shown to be related to non-atherosclerotic causes most of the time. The aim was to determine the serum lipid profile and the vascular risk factors for ischaemic stroke in a series of patients under 45 with an ischaemic stroke and to compare them with a series of controls of the same age.

METHODS

Ninety four consecutive patients with ischaemic stroke were compared with 111 controls of the same age recruited from a regional electoral list. Vascular risk factors were recorded and serum lipid profile was determined in all of them.

RESULTS

Multivariate analyses showed that low HDL cholesterol, male sex, smoking, hypertension, and oral contraceptives were risk factors for intracerebral arterial occlusion.

CONCLUSION

Low HDL cholesterol was the only serum lipid index to be associated to an increased risk of stroke in this population. Low HDL cholesterol must be considered in the care management of young patients regardless of the detectable presence of atherosclerosis.

Cardiovascular mortality of Chinese in New York City

To determine cardiovascular disease mortality among Chinese migrants in New York City and compare it to both that of residents in China and whites in New York City, mortality records for 1988 through 1992 for New York City and the 1990 US census data for New York City were linked. Age-specific death rates for urban China, reported by the World Health Organization, were used for comparison. The results show that male and female Chinese residents in New York City had lower mortality rates for all causes and total cardiovascular disease than did either New York City whites or Chinese in China. Coronary heart disease deaths among New York City Chinese were intermediate between Chinese in China (lowest) and New York City whites (highest). Stroke death rates for New York City Chinese were substantially lower than those in China and, in general, were similar to those for New York City whites. However, New York City Chinese had higher death rates for hemorrhagic stroke and lower for atherosclerotic stroke than did New York City whites. In conclusion, cardiovascular mortality rates among Chinese migrants in New York City fall below those of both Chinese in China and whites in New York City.

Carotid atherosclerosis in renal transplant recipients: relationships with cardiovascular risk factors and plasma lipoproteins

BACKGROUND

Renal transplant recipients have an increased incidence of cardiovascular disease, but less data exist about cerebrovascular atherosclerosis. In this study, we assessed the prevalence of carotid lesions as evaluated by B-mode ultrasonography in a group of renal transplant recipients, and we evaluated univariate and multivariate relationships between common risk factors and plasma lipoproteins and carotid lesions.

METHODS

Fifty-seven renal transplant recipients and 113 age- and gender-matched controls underwent a complete clinical visit for the evaluation of risk factors present. In all subjects, a blood sample was collected for lipoprotein determination, and an ultrasound high-resolution B-mode imaging examination of the common carotid arteries was performed.

RESULTS

We found that among renal transplant recipients, there was a significantly increased prevalence of subjects with plaque in comparison with controls (24.6% vs. 6.2%, P<0.001). At multiple analysis, carotid lesions were independently associated with age, hypertension, diabetes, smoking habit, and the presence of cardiovascular disease in controls and with age and hypertension in renal transplant recipients. Neither the lipid profile nor the presence of dyslipidemias was related to carotid score in renal transplant recipients, whereas a nonsignificant trend was observed in controls. Finally, in transplant patients, we did not find any association between carotid lesions and high-density lipoprotein subfractions.

CONCLUSIONS

Age and hypertension are the main predictors of extracranial cerebrovascular atherosclerosis after renal transplantation. Because carotid lesions may represent a useful predictive marker of clinical events in nontransplant subjects, carotid artery evaluation by B-mode ultrasound might be routinely included in the management of renal transplant patients.

Low serum cholesterol as a risk factor for hemorrhagic stroke in men: a community-based mass screening in Okinawa, Japan

The relation between the level of total serum cholesterol and stroke is controversial. The relation between serum total cholesterol and subtypes of stroke was examined in the participants of a community-based mass screening program in Okinawa, Japan. A total of 38,053 subjects, whose serum level of cholesterol had been determined during a mass screening carried out in 1983, were examined to see whether they had experienced stroke during a 3-year period from 1988 to 1991. Of them, 315 subjects aged 33-93 years (174 men, 141 women) had had a stroke during that period. The types of stroke were cerebral infarction in 164, cerebral hemorrhage in 111, subarachnoid hemorrhage in 19, and others in 21. In men, the odds ratio of cerebral hemorrhage was 0.71 (95% confidence interval, 0.55-0.95), and the odds ratio of cerebral hemorrhage associated with serum level of cholesterol < or =167 mg/dl, 168-191 mg/dl, 192-217mg/dl, and > or =218mg/dl were 1.00 (reference), 0.70 (0.38-1.30), 0.77 (0.55-1.08), 0.73 (0.56-0.96), respectively. Lower serum cholesterol was an independent predictor of cerebral hemorrhage in men.

Suppression of endothelin-3-induced nitric oxide synthesis by triglyceride in human endothelial cells

Reduced endothelium-derived nitric oxide (NO) production characterizes several vascular diseases. This study examined the effect of triglyceride on NO production induced by endothelin-3 (ET-3) in cultured human umbilical vein endothelial cells. Triglyceride-rich human plasma obtained after a high-carbohydrate diet with white wine was used in an ex vivo study. The plasma triglyceride fraction was found to consist of large amounts of palmitic and oleic acids detected by gas-liquid chromatography. Therefore, the effect of synthetic tripalmitin and triolein emulsion on NO production was also examined. ET-3 stimulated NO and guanosine 3',5'-cyclic monophosphate production and increased cytosolic Ca2+ levels in the endothelial cells (ECs). After incubation of the ECs with the triglyceride-rich plasma for 2 h, these responses to ET-3 were ameliorated in a triglyceride concentration-dependent manner (50-200 mg/dl). A synthesized emulsion of tripalmitin (100 mg/dl) and triolein (100 mg/dl) also blunted the responses to ET-3. Neither endothelial constitutive NO synthase mRNA expression nor its protein level was affected by treatment with triglycerides. These results suggest that triglyceride suppresses ET-3-induced NO synthesis in human ECs by inhibiting cytosolic Ca2+ elevation.

Lipoprotein disorder in brain infarction and hemorrhage

The cholesterol, triglyceride, and apolipoprotein B content of very low-, intermediate-, low-, and high-density lipoprotein fractions (separated by ultracentrifugation) and plasma were measured in healthy controls and patients with atherothrombotic infarction (26), lacunar infarction (26), and brain hemorrhage (14). In both atherothrombotic and lacunar infarction, increased plasma and low-density lipoprotein apolipoprotein B and a decreased low-density lipoprotein cholesterol/apolipoprotein B ratio were noted. In brain hemorrhage patients, a decreased ratio was also observed. These findings suggest that increased small dense low-density lipoprotein is a characteristic risk factor for atherothrombotic and lacunar infarction.

Genetic risk factors and ischaemic cerebrovascular disease: role of common variation of the genes encoding apolipoproteins and angiotensin-converting enzyme

DNA polymorphisms in genes encoding apolipoproteins (apo) A-I, C-III, B and E and angiotensin-converting enzyme (ACE) have been proposed to be associated with the risk of coronary artery disease (CAD). We studied whether the same genetic markers would also be associated with the occurrence and extent of atherosclerosis in cervical arteries. DNA samples from 234 survivors of stroke or a transient ischaemic attack aged 60 years or less were examined. The presence of atherosclerosis was assessed using aortic arch angiograms. The SstI polymorphism of apoA-I/C-III gene locus, the XbaI polymorphism of apoB gene, common apoE phenotypes and the insertion/deletion polymorphism of the ACE gene were analysed. The allele frequencies of the apoA-I/C-III, apoB, apoE or ACE gene did not differ between the groups with (n = 148) or without (n = 85) cervical atherosclerosis. However, when patients with at least one apoE4 allele and one X2 allele of apoB were combined and compared with those without either of them (E2E3 or E3E3 and X1X1), a significant association with the presence of cervical atherosclerosis was found (P = 0.03). The patients having the E2E3 phenotype had a significantly elevated serum triglyceride level compared with those with the E3E3 phenotype (P = 0.03). Serum high-density lipoprotein (HDL) cholesterol was lower in the patients with the E2E3 phenotype than in those with the E3E3 and E3E4 (P = 0.01 and P = 0.06, respectively). The apoB or ACE genotypes were not significantly associated with serum lipid or lipoprotein levels. There was no association between the ACE gene polymorphism and the occurrence of hypertension. In conclusion, the interaction of common apoB and apoE alleles may increase the risk of atherosclerosis in cervical arteries.

The inverse relation of average population blood pressure and stroke mortality rates in the seven countries study: a paradox

This study attempts to explain the unexpected finding of an inverse population (ecological) relationship between mean systolic blood pressure levels and stroke death rates in 25 years follow-up of the Seven Countries Study, a cross-cultural study of cardiovascular disease. Sixteen cohorts of all men aged 40-59 in seven countries (one cohort in the USA, two in Finland, one in the Netherlands, three in Italy, two in Croatia (former Yugoslavia), three in Serbia (former Yugoslavia), two in Greece, two in Japan) were surveyed from 1958 to 1964. Risk factors and personal characteristics were measured and follow-up for vital status and cause of death was then carried out over 25 years. Analyses were based on comparisons of mean levels of risk factors and death rates within and among the 16 cohorts. Mean entry population levels of systolic blood pressure among the cohorts were strongly and inversely related with their 25-year stroke death rates (R -0.55; CI -0.81 and -0.06; p = 0.0276). Within cohorts in contrast, the individual relation of blood pressure and stroke was strongly positive and significant in 14 of the 16 cohorts. Mean population levels of serum cholesterol were inversely and strongly related to stroke death rates (R -0.79; CI -0.92 and -0.46; p = 0.0003), while the partial correlation coefficient of systolic blood pressure, computed in models including serum cholesterol, became small and not significant (-0.05; CI -0.55 and +0.48; p = 0.8537). Age at death for stroke (average 68.9 +/- 7.1 years) was significantly higher than age at dath from myocardial infarction and sudden death (average 65.8 +/- 7.8 years) suggesting a competition effect between the conditions. Multivariate models including population average systolic blood pressure and serum cholesterol provided no added explanation for the lack of direct and significant relationship of population blood pressure with stroke death rates. They were based on these variables: age at stroke death, age at myocardial infarction death or and sudden death, death rates from myocardial infarction and sudden death, the interaction term of systolic blood pressure with serum cholesterol and the multivariate coefficients for systolic blood pressure from Cox models run in individuals. Similar findings were obtained using diastolic instead of systolic blood pressure and excluding the Japanese cohorts. The paradox of the inverse ecologic relation of population blood pressure and stroke mortality and a direct relation for individual is only partly explained by the cofounding effect of population mean serum cholesterol levels. An effect of low cholesterol levels on excess stroke mortality cannot be excluded. A major limitation of the study was our inability to segregate thrombotic from heamorrhagic strokes.

Natural history, prognosis, and lipid abnormalities of idiopathic ischemic childhood stroke

A study was performed to assess the natural history, prognostic factors, and lipid and apolipoprotein abnormalities of idiopathic ischemic childhood stroke. A case series of 42 children, retrospectively identified with idiopathic ischemic strokes, were reassessed an average of 7.4 years (range, 1 to 19 years) after presentation. Patients were interviewed and examined, and fasting serum was obtained for lipid and apolipoprotein analysis. Poor outcome was defined as moderate to severe hemiparesis, special educational needs, epilepsy, recurrent stroke, or stroke-related death. Eighteen (43%) of the patients had a poor outcome. Among them were moderate to severe hemiparesis in 14 (78%), recurrent strokes in seven (39%), and one death. Poor outcome was evident early in their clinical course. Independent of outcome, lipid abnormalities including an elevated triglyceride and low-density lipoprotein cholesterol, and a depressed high-density lipoprotein cholesterol were seen in one third of all patients. A depressed ratio of apolipoprotein A-1 to apolipoprotein B (using adult normative values) was seen in half of the entire cohort. Clinical features of children with unexplained ischemic strokes at presentation and their subsequent course are described. Significant risk factors for a poor outcome include (1) persistence of hemiparesis 1 month after the stroke, (2) cortical as opposed to subcortical location, and (3) bilateral occlusive disease with telangiectasia on cerebral angiography. Previously described risk factors for an unfavorable prognosis, including occurrence during infancy and presentation with seizures, were not substantiated. Lipid abnormalities occur at an increased frequency in children after unexplained ischemic strokes. Prospective assessment of lipoprotein profiles are needed to further assess clinical significance. Assessing apolipoproteins may provide further insight than lipid values alone.

Prevalence and outcome of symptomatic carotid lesions in young adults. National Research Council Study Group

OBJECTIVE

To estimate the prevalence and outcome of symptomatic internal carotid artery lesions in young adults.

DESIGN

Multicentre hospital based observational study with five year follow up.

SETTING

Seven neurological departments in northern and central Italy.

SUBJECTS

240 patients (115 men) aged 15-44 with a recent transient ischaemic attack or stroke in the carotid territory.

MAIN OUTCOME MEASURES

(a) Prevalence of symptomatic internal carotid artery stenosis or occlusion detected by continuous wave Doppler ultrasonography at entry; (b) incidence rates of cerebral, cardiac, and non-vascular death; non-fatal stroke; and non-fatal myocardial infarction.

RESULTS

Carotid stenoses of 50-99% and occlusions were found in 38 patients (15.8%). Both conditions were significantly more frequent in patients aged over 35 and in those with hypertension, diabetes mellitus, and stroke at entry. The standardised mortality ratio at five years was 10.5 (95% confidence interval 5.0 to 19.3). Survival of patients with stenoses of 0-49% and occlusions was significantly better than that of patients with stenoses of 50-99%. Carotid stenosis of 50-99% was an independent predictor of death (hazard ratio 7.9; 95% confidence interval 2.2 to 29) and non-fatal stroke (hazard ratio 7.4; 1.5 to 37.4).

CONCLUSIONS

The prevalence of carotid stenosis or occlusion in young adults after a cerebrovascular event is low. Though patients with high grade symptomatic carotid stenosis are at risk of non-fetal and fetal events, patients with internal artery occlusion apparently have a benign prognosis.

Wall thickening of carotid and femoral arteries in male subjects with isolated hypercholesterolemia. PCVMETRA Group. Prevention Cardio-Vasculaire en Medecine du Travail

This study was performed to determine whether hypercholesterolemic men had increased large artery intima-media thickness (IMT), a potential surrogate measure of atherosclerosis, compared to normocholesterolemic controls. The measurements were performed in the far walls of common carotid and femoral arteries with non-invasive automatic computerized ultrasonic technique in 101 asymptomatic men (28-60 years) of whom 40 were normocholesterolemic (total cholesterol < 5.2 mmol/l, controls), 25 had borderline hypercholesterolemia (5.2 < or = total cholesterol < 6.2 mmol/l, group 1) and 36 had hypercholesterolemia (total cholesterol > or = 6.2 mmol/l, group 2). All the subjects had no other traditional risk factors, except smoking. Carotid and femoral IMT were significantly increased in group 2 (P < 0.01) but not in group 1 compared to controls. When all subjects were pooled for analysis, carotid and femoral IMT were correlated (r = 0.47, P < 0.001) and increased with total cholesterol (r = 0.35, P < 0.001) and LDL cholesterol (r = 0.33, r = 0.34, respectively; P < 0.001). Carotid and femoral IMT increased with age in each group: controls, r = 0.46, P < 0.01 and r = 0.50, P < 0.001, respectively; group 1, r = 0.42, P < 0.05; group 2, r = 0.48, P < 0.01, and r = 0.59, P < 0.001, respectively. At the carotid and femoral sites, the regression slopes between age and IMT were steeper in group 2 than in controls (P < 0.01). Thus, hypercholesterolemia was associated with diffuse large artery wall thickening, whose presence might be useful in the identification of those hypercholesterolemic individuals most prone to developing atheromatous changes, in the decision to treat, and in the monitoring of lipid-lowering treatment.

Association of carotid atherosclerosis and left ventricular hypertrophy

OBJECTIVES

This study was undertaken to determine the prevalence of carotid atherosclerosis in a large group of asymptomatic hypertensive and normotensive adults and to examine its relation to the presence of left ventricular hypertrophy.

BACKGROUND

Both electrocardiographic and echocardiographic left ventricular hypertrophy predict an increased risk of cardiovascular events and mortality, including cerebrovascular disease, but the mechanism of association is unknown.

METHODS

Four hundred eighty-six (277 normotensive and 209 untreated hypertensive) adults, free of clinical evidence of cardiovascular disease, were studied prospectively with echocardiography to determine left ventricular mass and carotid ultrasound to detect atherosclerosis and to measure common carotid artery dimensions.

RESULTS

Carotid atherosclerosis was present in 16% of normotensive and 23% of hypertensive participants (p < 0.05) and was associated with older age, higher systolic and pulse pressures and larger left ventricular mass index ([mean +/- SD] 91 +/- 19 vs. 82 +/- 18 g/m2, p < 0.0001). The difference in mass persisted after adjustment for baseline differences in age and blood pressure. Subjects with left ventricular hypertrophy were twice as likely to have carotid atheromas (35% vs. 18%, p < 0.01). Logistic regression analyses, including standard risk factors, indicated that only age and left ventricular mass index independently predicted the presence of carotid plaque, both in the entire study group and when normotensive and hypertensive subjects were considered separately.

CONCLUSIONS

We believe that the present study provides the first evidence that higher left ventricular mass as detected by echocardiography is associated with the presence of carotid plaque. The association between cardiac hypertrophy and systemic atherosclerosis may contribute to the pathogenesis of the high incidence of vascular events that is well documented in patients with left ventricular hypertrophy.

Lipoprotein(a) as a correlate of stroke and transient ischemic attack prevalence in a biracial cohort: the ARIC Study. Atherosclerosis Risk in Communities

Although both mean lipoprotein(a) [Lp(a)] concentration and national stroke prevalence estimates are consistently higher in American blacks than in whites, no information exists on the relationship of Lp(a) and stroke prevalence in African-Americans. Associations of Lp(a) with stroke or transient ischemic attack (TIA) are addressed in this report for 15,160 participants--4160 blacks and 11,000 whites--in the Atherosclerosis Risk in Communities (ARIC) Study. Lp(a) was measured in ARIC as its total protein component by double-antibody enzyme-linked immunosorbent assay (ELISA) for apo(a) detection. Self-reported stroke/TIA history was assessed as part of a standardized questionnaire, and resulted in age-adjusted stroke/TIA prevalences of 3.0% in blacks (n = 120) and 2.0% in whites (n = 222). Overall, mean Lp(a) protein levels were markedly higher for blacks than for whites (160.5 versus 81.6 micrograms/mL, respectively), and were statistically significantly higher among individuals reporting stroke/TIA history for both races (191.3 versus 159.6 micrograms/mL in blacks; 100.6 versus 81.2 micrograms/mL in whites). Multivariable logistic regression analysis for the association of Lp(a) protein with stroke/TIA status yielded a prevalence odds ratio (OR) (95% confidence intervals) of 1.17 (1.05, 1.30) overall (based on one standard deviation difference, 108.2 micrograms/mL, in Lp[a] protein). Race-specific ORs, after adjustment for the same covariates, were equivalent for blacks [OR = 1.17 (0.99, 1.39)] and whites [OR = 1.19 (1.04, 1.36)]. These data suggest that Lp(a) is an independent risk factor for stroke/TIA in both blacks and whites, and that the relative risk of stroke/TIA associated with Lp(a) protein does not vary by race.(ABSTRACT TRUNCATED AT 250 WORDS)

The prevention of cardiovascular disease. Emphasis on secondary prevention

Atherosclerosis is a progressive disease affecting all major arteries. Clinical evidence of atherosclerosis increases the risk of subsequent morbid and mortal events fivefold to sevenfold over the next 5 to 10 years. The same risk factors contribute to the initial development of CVD events as to their recurrence. Both coronary and noncoronary events, such as stroke or PAD, reflect the severity of the underlying atherosclerotic process and strongly predict future excess CVD morbidity and mortality. Short-term and long-term survival depends on modifying the risk factors that contribute to CVD events. Although absolute proof of benefit for secondary prevention does not exist for all risk factors, the data from primary prevention trials and the secondary prevention trials that have been done argue strongly for aggressive intervention. Benefit has been demonstrated for smoking cessation, cholesterol reduction, and blood pressure control. Selected patients may benefit from additional medical, procedural, or surgical interventions to prolong life, such as beta-blocking agents, aspirin, or carotid endarterectomy. Many secondary prevention measures are a cost-effective way to reduce the substantial morbidity and mortality due to CVD. Contrary to primary prevention, even modest treatment effects from secondary prevention efforts can benefit large numbers of patients. Finally, secondary prevention may be more successful because patients with clinical evidence of CVD may be more highly motivated than their healthy counterparts to make and maintain lifestyle changes.

Transient ischemic attacks, risk factors, and precerebral color doppler angiosonography

The aim of this study was to ascertain the importance of color-coded Doppler sonography (CCDS), a noninvasive examination technique, in early detection of atherosclerotic lesions in precerebral arteries. CCDS was utilized in a group of patients with one or several transient ischemic attacks (TIA) and in a group of non-TIA (NTIA) cases, so that the degree of atherosclerotic lesions of precerebral vessies in TIA and NTIA patients might be compared. The presence of risk factors for cerebrovascular disease (CVD) was compared in both groups as well. We examined 87 patients with TIA (38 women and 49 men), aged 19-86 years (mean, 60.97 ± 11.97 years) and 48 NTIA patients (22 women and 26 men), aged 35-85 years (mean,60.04 ± 9.37years). No statistically significant differences in age and gender were found between the groups. A significant difference was found between the common carotid artery intimal-medial thickness (CCA IMT) in TIA patients (CCA IMT right + left = 1.12 ± 0.44 mm) and NTIA patients (CCA IMT right + left = 0.91 ± 0.32 mm) (p < 0.0001). A positive significant association was found between both groups in the number of different plaques (p < 0.0001) and the number of stenoses (p < 0.0001). When risk factors were compared, the difference between TIA and NTIA groups was statistically significant in regard to high-density lipoproteins (p < 0.002), total cholesterol (p < 0.004), and blood glucose concentrations (p < 0.013), as well as systolic blood pressure (p < 0.011). In conclusion, Doppler sonographic changes in precerebral arteries were present in the TIA group in spite of the fact that both groups had identical risk factors for CVD. CCDS is a valuable aid for early detection of TIA patients who have a significant risk of developing brain infarction.

Relationship of dietary intake to hospital admission for coronary heart and vascular disease: the NHANES II national probability study

After excluding 2,908 subjects (25% of the cohort) whose diets had changed, possibly as a consequence of disease discovery, in 8,679 individuals from the NHANES II national probability study, our specific aim was to determine which nutritional factors were significant independent contributors to overnight hospitalization with coronary heart and vascular disease (CHD). Covariance adjustments were made for multiple sociodemographic, educational, geographic factors, total cholesterol, high-density lipoprotein cholesterol (HDL-C), race, age, sex, and relative ponderosity (obesity). After these adjustments, linoleic acid (p = 0.049) and alcohol (p = 0.017) were independently inversely associated with CHD hospitalizations; cigarette smoking (p = 0.054) was positively associated. Relative risk for CHD hospitalization was 1.0 for linoleate 0-6 g/day, 0.72 for 6-11.59 g/day, and 0.49 for > or = 11.6 g/day, p < or = 0.01. Relative risk for CHD hospitalization was 1.0 for no coffee intake, 0.6 for regular coffee, 1.8 for regular coffee plus decaffeinated coffee, 2.6 for decaffeinated coffee, and 5.2 when decaffeinated coffee was drunk by virtue of physicians' advice, p < or = 0.001. Unlike our extensive exclusions (25% of the cohort) for diet change, we did not exclude any subjects on the basis of self-directed or physician-recommended changes in smoking habits of initiation of decaffeinated coffee use, following, or as a consequence of disease discovery. We speculate that the relationship of decaffeinated coffee to CHD reflects behavior change after CHD hospitalization. Dietary cholesterol (p = 0.038) was an independent positive predictor of serum total cholesterol.(ABSTRACT TRUNCATED AT 250 WORDS)

Factors associated with occurrence of large vessel and lacunar cerebral infarctions

A stroke registry was developed to determine the localizing value of various clinical data. Adequate localization was achieved in 98% of 246 patients with infarcts. Among 212 male patients with cerebral infarcts not due to cardiogenic embolism or an unusual etiology, there were 152 with large-vessel and 59 with lacunar infarcts. Logistic regression analysis of factors associated with large vessel and lacunar stroke identified myocardial infarction on ECG as the only statistically significant variable; its presence was associated with an odds ratio for lacunar infarction of 0.19 (95% confidence interval 0.06-0.66) (P = 0.009). Logistic regression analysis of factors associated with anterior and posterior circulation large vessel stroke identified pack years of smoking as the only statistically significant variable; the odds ratio for posterior circulation infarction for a 10-year increment in pack years of smoking was 0.83 (95% confidence interval 0.73-0.94) (P = 0.0035).

Association of serum antibodies to heat-shock protein 65 with carotid atherosclerosis

Arteriosclerotic lesions can be induced in normocholesterolaemic rabbits by immunisation with heat-shock protein (hsp) 65, a stress protein expressed in high concentrations in human atherosclerotic lesions. If an immune reaction to hsp65 also plays a part in human atherogenesis, it should be possible to detect anti-hsp65 antibodies in patients with atherosclerotic lesions. To study the possible relation between immune reaction to hsp65 and atherosclerosis, 867 normal inhabitants of South Tyrol, aged 40-79 years, were selected randomly for determination of serum antibodies against hsp65, simultaneous sonographic assessment of carotid atherosclerotic lesions, and evaluation of established risk factors--ie, blood cholesterol, hypertension, smoking, diabetes mellitus, and obesity. Autoantibodies to nuclear antigens, thyroid antigens, and rheumatoid factors were also measured. Serum anti-hsp65 antibodies were significantly (p < 0.05) increased in subjects aged 60-79 years with carotid atherosclerosis compared with those without lesions, and increased antibody concentration was independent of age, sex, and other established risk factors. On the other hand, the incidence and titres of autoantibodies did not correlate with carotid atherosclerotic lesions. Our data provide the first evidence of a strong correlation between anti-hsp65 antibodies and carotid atherosclerosis, suggesting that hsp65 might be involved in the pathogenesis of atherosclerosis.

Plasma lipids and lipoproteins in subtypes of stroke

We determined plasma lipid and lipoprotein concentrations in 131 patients (95 males, 36 females, mean age 71 years) 6 months after acute stroke onset. Compared to a reference population, the alterations of plasma lipid concentrations in stroke patients were moderate. However, the stroke patients had higher levels of triglyceride and lipoprotein (a) and lower concentrations of cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol. Patients with different subtypes of stroke showed significant differences when compared with each other by analysis of covariance (with adjustment for age, sex, smoking, hypertension and diabetes). Patients with carotid or vertebral artery disease had the higher levels of cholesterol, triglyceride and apolipoprotein B, whereas high density lipoprotein triglyceride concentrations were higher in patients with cardioembolic infarcts.

Rationale and design for the Asymptomatic Carotid Artery Plaque Study (ACAPS). The ACAPS Group

An NHLBI-sponsored randomized, double-masked, placebo-controlled, multicenter clinical trial is underway to test the efficacy of the lipid-lowering agent lovastatin and/or the antithrombotic agent warfarin in slowing the progression of early carotid atherosclerosis--as defined by ultrasonographic intimal-medial arterial wall thickening--in a high-risk, asymptomatic population consisting of 919 men and women aged 40-79 years with moderately elevated serum LDL-cholesterol. The Asymptomatic Carotid Artery Plaque Study's (ACAPS) factorial design permits evaluation of each of the two treatments alone as well as assessment of the treatments in combination with each other over a 2.5- to 3.0-year treatment period. Randomized participants receive either 20-40 mg/day lovastatin or lovastatin placebo and either 1 mg/day (minidose) warfarin or warfarin placebo. All participants were encouraged to take low-dose (81 mg/day) aspirin. The primary outcome is the ultrasonographic measurement of the mean of maximum intimal-medial thickness (IMT) across up to 12 preselected segments in the carotid arteries. The secondary outcome of the trial measures the single maximum IMT measurement among the same preselected carotid artery segments. This report describes the rationale for ACAPS, its design, and some baseline characteristics of the study population.

Carotid stenosis is a powerful predictor of a positive exercise electrocardiogram in a large hyperlipidemic population

Hypercholesterolemia is a major risk factor in coronary heart disease (CHD) and ischemic stroke. However, there is no general agreement on the usefulness of systematic screening of patients with hyperlipidemia by stress exercise electrocardiogram (ECG). The feasibility of this approach would depend on selecting patients with a high risk of CHD, since the sensitivity and specificity of the test depends on the prevalence of the disease. In view of the association of CHD and ischemic stroke, we undertook a study to determine whether the presence of atherosclerosis in the carotid arteries was predictive of a positive exercise ECG in a group of 778 asymptomatic patients referred to their hyperlipidemia. We a much higher percentage of positive exercise ECG in patients with carotid atherosclerosis in our ultrasonographic examinations. In a multiple regression analysis which included 13 parameters (age, sex, body mass index, arterial blood pressure, lipid parameters, serum level of glucose, smoking status and the severity of carotid lesions), the strongest predictors of a positive exercise ECG test were age (P = 0.014) and the degree of carotid atherosclerosis (P = 0.010). We therefore conclude that hyperlipidemic patients with atherosclerotic lesions on carotid arteries would benefit most from screening by the exercise ECG.

Ischemic stroke. How to keep the first one from happening

The prevention of stroke has undenied merit. Recognition of stroke-inducing conditions (eg, cardiac diseases associated with embolism, polycythemia) provides opportunities for specific prevention strategies. For a larger number of patients, however, risk factors for degenerative vascular disease should be addressed. The evidence for efficacy is strongest for treatment of hypertension, and smoking cessation also reduces the risk of stroke. The value of treatment of hyperlipidemia in reducing the incidence of a first stroke remains to be demonstrated. Optimal management of carotid bruit and asymptomatic stenosis will be clarified by results of ongoing clinical trials. On the basis of available data, use of aspirin by healthy persons without risk factors cannot be recommended as a method for preventing a first ischemic stroke.

Relative protection from cerebral atherosclerosis of young patients with homozygous familial hypercholesterolemia

It is well known that hypercholesterolemia is correlated with coronary atherosclerosis, but no definite information is available on its association with cerebrovascular atherosclerosis. We studied 10 young patients (age 3-32 years) with homozygous familial hypercholesterolemia (FH), together with 3 normal relatives as healthy controls. Extra- and intracranial Doppler examination, MRI and cerebral blood flow by SPECT and 99mTc-HM-PAO were performed on all. Six out of 10 patients already had signs and symptoms of coronary heart disease, but all patients were free from ischemic brain lesions, as small as detectable at MRI, and had normal cerebral blood flow. Two patients presented significant stenosis of the carotid arteries at Doppler examination. Young patients with homozygous FH have early and clinically evident coronary atherosclerosis, while overt disease in the cerebral district is delayed despite the extremely elevated plasma cholesterol concentration. This was also confirmed by the autopsy of two patients, who died after the study and whose cerebral arteries were totally free from atherosclerotic lesions. The age, at which flow-reducing atherosclerotic lesions develop in hypercholesterolemic patients, differs with regard to the arterial district involved.